A vehicle power transmission device is known that includes a hydraulic power transmission device having an input-side rotating member disposed with a plurality of pump blades and an output-side rotating member disposed with a plurality of turbine blades receiving a fluid flow from the pump blades, and a power transmission mechanism transmitting power input to an input shaft from the hydraulic power transmission device to a subsequent stage, in a power transmission path between an engine and drive wheels. For example, this corresponds to those described in Patent Documents 1 to 4.